The device_unregister call in thermal_zone_device_unregister causes the
thermal_zone_device structure to be freed before the call to free the
dynamically allocated attribute groups. This leads to a kernel panic.

Furthermore, the 4 calls to free the trip point attribute structures
occur before the call to unregister the device, leading to a kernel
panic when sysfs attempts to access the attributes to remove them.

Here is an example of a kernel panic when the cpu thermal zones are
removed upon cpu offline:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: strlen+0x0/0x20
<snip>
Call Trace:
   ? kernfs_name_hash+0x17/0x80
   kernfs_find_ns+0x3f/0xd0
   kernfs_remove_by_name_ns+0x36/0xa0
   remove_files.isra.1+0x36/0x70
   sysfs_remove_group+0x44/0x90
   sysfs_remove_groups+0x2e/0x50
   device_remove_attrs+0x5e/0x90
   device_del+0x1ea/0x350
   device_unregister+0x1a/0x60
   thermal_zone_device_unregister+0x1f2/0x210
   pkg_thermal_cpu_offline+0x14f/0x1a0 [x86_pkg_temp_thermal]
   ? kzalloc.constprop.2+0x10/0x10 [x86_pkg_temp_thermal]
   cpuhp_invoke_callback+0x8d/0x3f0
   cpuhp_down_callbacks+0x42/0x80
   cpuhp_thread_fun+0x8b/0xf0
   smpboot_thread_fn+0x110/0x160
   kthread+0x101/0x140
   ? sort_range+0x30/0x30
   ? kthread_park+0x90/0x90
   ret_from_fork+0x25/0x30

This patch moves the kfree calls to clean up the dynamic attributes to
the thermal_class's thermal_zone_device release function.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Tested-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: NJacob von Chorus <jacobvonchorus@cwphoto.ca>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

The thermal core does not use the ability to look up pointers by ID, so
convert it from using an IDR to the more space-efficient IDA.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Reorganize code to reflect better placement.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

As a safety check, this patch changes thermal
core to check for pointer content size, instead of type size,
while allocating memory.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Improve description and keep 80 columns limit.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Removing several style issues in thermal code code.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply removing useless returns of void functions.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Pass through the code to remove check suggested by
checkpatch.pl (alignment to parenthesis):
CHECK: Alignment should match open parenthesis

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Remove style issue:
CHECK: Comparison to NULL could be written "!__find_governor"
+	if (__find_governor(governor->name) == NULL) {

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simplify the GPL notice by removing the FSF address.
No need to track FSF location in this file.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

comment describing the section with function to handle
registration, unregistration, binding, and unbinding of
thermal devices.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply marking the power actor section and adding a
comment describing it.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply marking the main update loop section and adding a
comment describing it.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

moving the helper function to closer to similar functions.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Given that this is simple wrapper, adding the inline flag.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Moving the helper to closer where it is used.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Removing style issues on __bind() and its helpers.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Moving the helper to closer where it is used.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Moving the helper to closer where it is used.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply moving the helper to closer where it is actually used.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply aligning to parenthesis.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Given that idr is only used to get id for thermal devices
(zones and cooling), makes sense to move the code closer.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Organize thermal core code to group the functions
handling with governor manipulation in one single section.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Here we have a simple code organization. This patch moves
functions that do not need to handle thermal core internal
data structure to thermal_helpers.c file.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Reorganizing the code of helper functions to improve
readability and style, as recommended by checkpatch.pl.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This is a code reorganization, simply to concentrate
the sysfs handling functions in thermal_sysfs.c.

This patch moves the cooling device handling functions.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Make the to_cooling_device() macro available across
files in thermal core.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This is a code reorganization, simply to concentrate
the code handling sysfs in a specific file: thermal_sysfs.c.

Right now, moving only the sysfs entries of thermal_zone_device.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Cosmetic change in the sysfs handling functions, as
recommended by checkpatch.pl.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This patch checks the return value of all calls to *scanf.
The check is to simply match the number of expect inputs.

The current code does not do any recovery in case the
number of treated inputs are different than the expected.
Therefore, keeping the same behavior.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simply making this macro available to other thermal core
files.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This patch creates a helper to build a list of available governors.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Similarly to passive_store, policy_store now is split
between thermal core data structure handling and sysfs handling.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Split passive_store between sysfs handling and thermal
core internal data handling.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Given that cdevs sysfs properties are already registered using
the dev.groups, there is no need to explicitly call device_remove()
for each property.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Finally, move the last thermal zone sysfs attributes to
tz->device.groups: trips attributes. This requires adding a
attribute_group to thermal_zone_device, creating it dynamically, and
then setting all trips attributes in it. The trips attribute is then
added to the tz->device.groups.

As the removal of all attributes are handled by device core, the device
remove calls are not needed anymore.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This is a patch to allow adding groups created dynamically. For now we
create only the existing group. However, this is a preparation to allow
creating trip groups, which are determined only when the number of trips
are known at runtime.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Code reorganization to keep all the sysfs I/F of a thermal zone in the
same section.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Align to parentheses, removing checkpatch warning.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Fix style problem on create_trip_attrs();

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NEduardo Valentin <edubezval@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>